I blocked every application in the entire Office directory structure, and MS Word can still access the internet.
I used the program fab.exe (Firewall App Blocker) to add all the apps in the directories to Windows Defender with a couple clicks, and confirmed the apps were added as blocked in Windows Defender. I disabled everything available in Word in privacy options and the trust center. There is no block internet setting. (MS Office Pro 2019, with a personal account log-in).
I can still follow links in Word (they open in Edge), and I can still login to the Microsoft account (no Edge required) from Word.
So, how do I block Word from accessing the internet?